He who cannot put his thoughts on ice should not enter into the heat of dispute.

The aphorism warns that argument is not merely an exchange of reasons but a test of temperament. To “put his thoughts on ice” suggests the capacity to cool one’s immediate reactions—anger, vanity, the urge to win—and to suspend judgment long enough to examine claims clearly. Without that self-command, entering the “heat of dispute” turns discussion into combat: rhetoric replaces inquiry, and the disputant becomes captive to passion and pride. Read in a Nietzschean key, it also implies that intellectual strength includes mastery over one’s affects; the disciplined thinker can use conflict productively, while the undisciplined is consumed by it.